[dpdk-dev] Impossible to build external application if user build DPDK with "make config"

[Thomas Monjalon]

27/03/2020 10:14, Tom Barbette:
> CC'ing original participants as I don't see a way out of this.
> 
> Le 12/03/2020 à 13:04, Tom Barbette a écrit :
> > Hi all,
> > 
> > If the user follows the quick guide 
> > (http://core.dpdk.org/doc/quick-start/) DPDK will be compiled in the 
> > "build" folder.
> > 
> > However, external applications will always fail to build because 
> > RTE_SDK_BIN is strictly defined as $RTE_SDK/$RTE_TARGET, and 
> > mk/internal/rte.extvars.mk needs to find .config in $RTE_SDK_BIN.
> > 
> > Therefore please apply the patch at:
> > http://patchwork.dpdk.org/patch/9991/ that allows external apps to 
> > override $RTE_SDK_BIN.
> > 
> > Or (less preferable) modify the quick start guide to use something more 
> > standard that allows to build with external apps (eg use the menu or 
> > propose "make config T=x86_64-native-linuxapp-gcc 
> > O=x86_64-native-linuxapp-gcc" instead). It's much easier for external 
> > apps maintainer to refer to the DPDK tutorial for DPDK installation.

I don't understand the issue.
First of all, the external application should link an installed DPDK.
Then you should be able to set $RTE_SDK and $RTE_TARGET to fit
the installation directories.

Just checked doc/guides/linux_gsg/build_dpdk.rst
I see the whole build process with make is not correctly documented.
It should be:

1/
	make defconfig
	or
	make config T=x86_64-native-linux-gcc O=mybuild

2/	make -j4 O=mybuild

3/	make install O=mybuild DESTDIR=myinstall prefix=

4/	RTE_SDK=$(pwd)/myinstall/share/dpdk RTE_TARGET=x86_64-native-linux-gcc make -C myapp

Please can you confirm it works?